Abating foaminess in glues



Patented Oct. 26, 1937 UNiTED STATES PATENT OFFICE ABATING FOAMINESS INGLUES Lawrence Bradshaw, Bainbridge, N. Y.

No Drawing. Application April 23, 1935, Serial No. 17,853

11 Claims. (01. 12.4-23.8)

This process has for its obiectthe abatement double speed for tenminutes. During this period or prevention of foam in glues prepared fromthe volume of the glue may increase considerably, proteinous substancessuch as vegetable seed due to foaming. At the end of the beating periodmeals, with or without milk casein, blood albumen a second sample of 100c. c. of theglue is weighed,

and the like. and the decrease in weight determined, and cal- It isknown that glues made, for example, from culated as a percentage of theweight of the vegetable seed meals such as peanut meal, with originalglue. The greater the amount of foam, or without the admixture of caseinand/or blood the greater will be the percentage lossof weight albumen,together with lime and alkalies or salts of the standard volume of glue.In a second test 0 which in the presence of water, can produce free amixture of 98 parts of the glue with 2% of the alkalies, frequently havean undesirable tendselected substance, e. g. a soluble salt (togetherency to foam upon being mixed with water, esmaking 100 parts) are addedto the same amount pecially when the dry ingredients have been of wateras before, and stirred for 20 minutes mixed together and kept in storagefor a con- (the same procedure and same proportion of glue siderabletime or exposed to unfavorable condibase to water being used as in thefirst test) tions of temperature and humidity. Foamy and the weight ofthe standard volume of glue glues, from whatever source, are usuallydeficient determined. The glue is then beaten as before in mobility andcohesiveness, do not spread and a second sample weighed and thepercentage readily and evenly, and when applied to wood loss of weightdetermined. The difference beveneers and the like give inferior joints.tween the percentage loss of weight in the two 20 The present inventionrelates to a method of cases is a measure of the foam-abatementproabating or preventing foaming and improving 'duced by the particularsalt in the beating the general character of such foamy glues, andprocess. also includes mixtures (glue bases) as hereinafter In the sameway, by using equal weights of described. The method-consists in addingto the several different salts respectively in diflerent 25 dry gluebase certain soluble salts or other sublots of the same glue theirrelative foam-abating stances which I have found to possess marked power(in that particular glue) can be roughly foam-abating properties. Suchsubstances (one determined. or several) are, in general, preferablyincorpo- As' examples of the application of this test the rated in a drystate in the dry glue base, but may following may be given. It may benoted that 30 be added to the water in which the glue is to be wheresodium fluoride is mentioned in these exdissolved, or may be added inthe dry form or in amples, a commercial sodium fluoride made an aqueoussolution to the glue at any approslightly alkaline with sodium carbonatewas used, priate stage of the process of dissolving the glue. which inaqueous solution is feebly alkaline to I have found that, of the largenumber of waterlitmus. The calcium acetate used in these tests 35soluble substances commercially available, comwas the chemically puresalt which when disparatively few possess the foam-abating propersolvedin-water reacts alkaline to litmus, but a tv in marked degree, whilesome are entirely deless pure, commercial grade is also effective.

void of this property. As examples of the former may be mentioned theacetates and formates of Example 1 calcium, barium, strontium, copper,and man- The glue base consists of 4'? parts of soymeal,

ganese, while examples of salts which appear to 46 parts cottonseedmeal, 5 parts milk casein have practically no anti-foam value are theniand 2 parts trisodium phosphate. 100 parts of trates and citrates ofsodium and potassium. this base are dissolved in water with the aid of'l One method of determining approximately the parts of lime and 9 partsof caustic soda, with 45 relative potency of such salts in abating foamis the subsequent addition of 30 parts of sodium as follows-a weighedamount of the given glue silicate solution. A convenient mixingprocedure is added to a suitable known amount of water is as follows: To300 parts of water at about and stirred for 20 minutes in a glue kettlepro- F. in the glue kettle add parts of the glue 60 vided with astirring device rotating at a fixed powder and stir for two minutes. Add'7 parts of slow speed, say 60 revolutions per minute. At the limesuspended in 25 parts of water and stir for end of this time the weightof a standard volume ten minutes. Add 9 parts of caustic soda disof theglue (say 100 c. c.) is determined. The solved in 25 parts of water andstir two minutes. glue in the kettle is then subjected to a vigorous Add30 parts of sodium silicate solution (e. g.

55 beating or whipping by rotating the mixer at water glass of 41B.whichcontalns about 36% 5 of silicate and about 64% of water), and stirI fourminutes. Dilute with 30 parts of water and stir two minutes. Themixing is completed, in

twenty minutes. i Total water (in addition to that I present in thewater glass, about 19.2 parts) 380 beating (l. e. stirring at 120 R. P.M.) for minutes, afterwhich asecond 100 c. 'c.-samp1e. I was weighed.The percentage decrease :of weight.

was i'ound to be I I I In a secon'd :test, two parts of strontiumacetate were blended with ninety-eight parts or the:

- aforesaid glue base and the mixture dissolved tween 20% and 5.3%namely 14.7%, indicates .thereductionin-theamount. of foam;

Among other-salts which exhibit this property .and beaten asbefore. Thepercentage decrease oi weight amounted. to 5.3%,i (as comparedwith.

the'20% decrease without the strontium acetate added) showingthat the.strontium acetate has:

a strong ioam-abating action. Thedifierence be-.

in marked degree as indicated by the above methcdgwhenthey-are usedinplace of an equal weight (2%) of strontium ace'tate,maybe-mewj tionedcopper acetate, which gives a percentage Q I decrease of 3.3% andcalcium formats 6.4%.-

The foam-abetting power of various salts diners terials, in the abovemethod, were accompanied gy decreases in weight, respectively of 21.0%and It will be understood that these figures were obtained with theparticular glue described, and any change in the composition of the saidglue, such as the substitution of peanut meal for soymeal or cottonseedmeal, or the use of a more foamy or less foamy soymeal or peanut meal orthe use of a greater or lesser amount of casein, or of blood albumen, orthe use of different kinds or amounts of the alkali used in dissolvingthe glue, may change the figures. 'By way of illustration other examplesof glues may be given.

Example 2 Soymeal parts, peanut meal 45 parts, blood albumen 10 parts.This glue base was dissolved using the same chemicals and with thetreatment as described under Example 1, as far as the stage of dilutionwith water, at which stage parts of water were added in place of the 30parts used in Example 1. Total water 410 parts. particular glue base,this amount of water was needed to give the consistency andflowdesiged). In the foam test the percentage decrease of weightwas-found (without a foam abating agent added) to be 27.3%. when 2 partsof calcium acetate was incorporated into the glue base (as team abatingagent) and the glue dissolved and subjected to beating in precisely thesame way, the percentage decrease of weight was only 14.6%. Thediilerence between 27.3% and 14.6%, namely 12.7%, represents theimprovement.

' tate 2 parts.

(With this Soymeal parts, peanut meal 38 parts, trisodium phosphate, 2parts. Proceed, as in Ex- I ample 2, using the same chemicals; i'Iotalwater 110 parts. The value obtained in the {10am test was 43L6% whichwasreduced to 28.2% when 2- parts of calcium acetate weremixed into the dryI -Soymeal parts,'lime '4 parts. To 300 parts .oi= water at about,'70 F.add-100 parts of glue base. Stir-abouts minutes. Then add. 9 parts I Iof caustic soda, in 25 parts water, stir 3 minutes. I .I 16

Add: 15 parts sodium silicate-solution (of about 41. Bed,stir'Zminut'esI; -Add 2%-'parts ofa II mixture of equaivolumes'oi carbondisulphide I :andcarbontetrachloride, stir 5 minutes. Dilute I with'parts' water, stir 2 minutes. Total water;

390. parts (in addition to that present in: the

r water'giass). Inthe foam. test this glue showed a percentage decreaseor weight of 40.4, which was i r I a reduced to 23.8 when 2% of calciumacetate was I I I I incorporated in the glue base. I

EadmpleSi' I I ciumacetate omitted, the value 'was,23.,0%. i Thisexample represents-a casein-lime glue with only a comparatively smallproportion of peanut meal added, 1. e. the meal was two-fifths or thecasein tmpti...

Peanut meal 68 parts, lime 17 parts, sodium Example 7 The composition ofthe glue base and procedure used in dissolving it were the same as inExample 1, except that the sodium silicate was omitted. Total water 380parts. The value obtained in the 10am test was 16.3%. When 2 parts ofcalcium acetate were blended into the glue base the value obtained was8.8%.

The anti-foam salts are effective not only in glues in which freecaustic soda is used as a solvent (as in Examples 1 to 4) but also inglues where (as in Examples 5 to 7) alkaline salts such as sodiumcarbonate, trisodium phosphate and similar alkalis are employed. Theanti-foam compounds named in this specification show the strongesteiIect in glues of which the proteinous component of the adhesive baseconsists largely of vegetable seed meals. In glues rich in casein orblood albumen and which contain only minor amounts of the proteinousmeal, the abatement oi the foam is less pronounced.

No claim is made herein to the glues mentioned herein by way of exampleor to other glues containing vegetable seed meal, milk casein or bloodalbumen, which do not include the use of foamf Casein: 50 parts, peanutmeal 20 parts, lime 18' wparts, sodium carbonate 10 parts-,calciumwace-100 parts'o! this'glue base were" added to 250=parts at water at about60F. and I stirredior'about 5 minutes.= :The mass was then. allowed torest for about 30 minutes and finally; stirred: for about 5. minutes..In the foam test. I this glue gave'avalueof19;0%. withthe calwflvabating compounds of the groups speciiled herein.

The invention is not limited to adding the foam-abating salts as such,but includes salts which may be formed within the glue by theinteraction oi basic and acidic substances capable of reacting to formsuch salts. Thus, I have found that a part of the free lime used inExample 1, may be neutralized in the glue by the addition of an acidsuch as acetic acid, forming calcium acetate in situ. Thus in the mixingprocedure given above, an appropriate amount of the acid (preferablydiluted with water) may be added in the kettle at a suitable stage, forexample just after adding the lime. In another modiiication of theprocess an excess of lime may be used to provide for the formation of acalcium salt within the glue when the acid is added. Naturally theamoimt of acid used must not be sufficient to completely neutralize thelime and precipitate the glue. In practice, from 1 to 2% of acid hasbeen found to be sufficient. This method however, is less eifective thanthat in which the foam-abating salt is incorporated into the glue basebefore this is wetted. or the modifications in which the salt is addedto the water before the glue base or shortly after the glue base.

Solid acids, such as benzoic, citric of sulfanilic acids added to theglue, for example after mixing with water (excess lime or other alkalipreferably being present) are also to some extent, effective in abatingfoam.

As an example of my preferred method the following maybe given: About 2parts of the salt selected, say calcium formate or acetate, arethoroughly mixed with about 100 parts of the dry glue base. The basegiven in Example 1 is suitable. The mixture may then be dissolvedasdescribed in Example 1. It will be understood that any suitable methodof mixing the glue can be used, depending upon the particular glue base.

This example is given by way of illustration only. It will be understoodthat the amount of anti-foam salt to be used is not limited but may begreater or less depending upon the foaming properties of the base usedand the potency of the salt selected and its general chemical character.If highly hygroscopic salts are used, they are preferably added to thewater in which the glue a.

is to be dissolved, either as solids or as solutions.

In practice it is advantageous to make up the glue base in such a waythat the dissolving operation will be as simple as possible, wherebyliability to error in the glue-mixing operation is reduced. This is anadded advantage for incorporating the salts used to abate foam, duringthe making of the dry glue base.

Without limiting the invention to the compounds herein specifled, I givebelow a list of the more important salts and acids which I have ioundtopossess the property of abating foam in glues of the type abovementioned: The acetates, formates, butyrates, and propionates of Al,(NH4) Cd, Ca, Cu, Fe, Pb, Mg, Mn, Ni and Sr; ammonium benzoate; bariumacetate, formate and tartrate; and calcium lactate, malate and citrate.f the salts, those of the metalsCa, Sr and Ba (i. e. the alkaline earthmetals) with the acid radicals acetic or formic, arepreferred, thesebeing considerably more eilective than the others given. Of the solidacids which may be added to the glue base containing lime, benzoic andcitric are preferred. The present application has been restricted to theuse of salts of organic acids.

The term "foam-abating salt" as used in this case is intended to embracethe above mentioned salts and also salts produced by the interaction ofthe above mentioned free acids with lime and/or other alkalies presentin the glue base or added thereto during the glue-dissolving operation.The term "an alkaline substance" is intended to embrace one or aplurality of alkaline substances. The term a salt" likewise is intendedto cover one or several of the salts of the types indicated.

I claim:-

I. A process of preparing a liquid glue free from an excessive amount offoam, from a base containing a substantial proportion of a protelnousseed meal, which base if agitated with water in the absence offoam-abating agents. would exhibit a tendency to produce foam, whichprocess includes the herein described step of adding a foam-abating saltselected from the group consisting of the water-soluble organic acidsalts of aluminum, ammonium, barium, calcium, copper, iron, lead,manganese, nickel and strontium.

2. A dry glue base comprising a protelnous seed meal constituting atleast a substantial proportion of the protelnous component of said base,and which base would, in the absence of foamabating agents,.show asubstantial tendency to the formation of foam when being mixed withwater, together with a foam-abating salt selected from the organic acidsalts of aluminum, ammonium, barium, calcium, copper, iron, lead,manganese, nickel and strontium.

3. A dry glue base as in claim 2, in which the foam-abating salt issubstantially white.

4. A dry glue base containing a protelnous seed meal as a largecomponent, together with an organic acid salt of an alkaline earthmetal, the glue base being one that, in the absence of said organic acidsalt would exhibit a tendency to produce a foamy glue when mixed withwater.

5. A liquid gluecontaining the reaction products of a protelnous seedmeal with an alkali. together with a soluble acetate of an alkalineearth metal, the latter acting as a foam abater.

6. A dry glue base containing a protelnous seed meal as a largecomponent, together with an acetate of an alkaline earth metal.

7. A dry glue base containing a protelnous seed meal as a large part atleast of its protelnous component, which base if mixed with waterwithout a foam-abating agent, would exhibit a tendency to the formationof foam, said base also containing calcium acetate as a foam-abatingagent.

8. A- dryglue base containing protelnous seed meal as a substantialcomponent, which also contains lime and a ,free solid acid capable ofreacting with lime when water is added, to form a water-soluble calciumsalt.

9. A dry glue base as in claim 2, in which the foam abating salt is asoluble non-hygroscopic calcium salt of an organic acid.

10. A process as in claim 1 in which the foamabating salt specifiedtherein is a salt of a bivalent metal.

11. A process as in claim 1 in which the foamabating salt specifiedtherein is a salt of a metal having an atomic weight between about 52and about 66.

LAWRENCE BRADSHAW.

